The use of new techniques to study the evolution and filling incised valleys has provided,
over the years, important results was to understand how the coastal evolution of the Brazilian coastal
zone. In this context, this thesis aimed to study the evolution of the estuary Coreaú River, located in
the state of Ceará, in different time scales, is "Possible" (months, years), "Engineering" (years,
decades) and "Geology" (hundreds, centuries, millennio), proposed by Cowell et al (2003), with the
goal to assess whether changes /alterations over the years were significant or not in the estuary. As a
result, we obtained the first goal, using remote sensing techniques from image sensor TM, ETM+ and
OLI of Landsat 5, 7 and 8 and sensor LISS-3 of satellite ResourceSat-1 from 1985 to 2013, a change
minimal in relation to morphological changes along the estuary in the last 28 years (between Possible
scales and Engineering), there was an increase in this period of 0.236 km2 (3%) of the area, not
bringing significant changes to the estuary. Regarding sedimentation rate, corresponding to the
second goal, from the collection of nine witnesses, up to 1m deep and using radionuclídeo 210 Pb
along the estuary, we obtained a rate that ranged from 0,33 cm/year 1 cm/year (between scales
Geological and Engineering) near the mouth of the estuary, and with a quick sedimentation
perceived on the east bank of the river, where there are younger sediments toward the west margin.
Regarding the fulfillment, third and final goal from the sampling of testimonials to 18 m depth, using
the sampler Rammkernsonden (RKS), profiles and stratigraphic sections that helped understand
filling the valley section of the estuary of the Coreaú river were generated and that it is a fluvialmarine
estuary, filling the valleys formed in group Barriers in the last 10.000 years before present.
These analyzes and results serve as a basis for comparison with other estuaries, either fluvial,
fluvio-marine or marine, to better understand what the possible events that dominated sedimentation
along the coast of Brazil at diferent scales.
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